In view of these problems WO2004/111562 proposes to avoid contact reactions by arranging strands of ceramic fibres as a grating within a temperature stable frame, said strands providing a screen of fabric-like structure, having a warp- and weftlike arrangement of strands within said frame. Such a strand-based grating turned out to have the draw-back, that ceramic strands will resinter considerably under high temperature conditions and become brittle; especially the intersecting fabric-structure in combination with brittle strands leads to breakage of strands in the support-areas of the workpiece, even if the supported workpiece is affected only by light vibrations.
JP 07 133 166 proposes to encase bodies of carbon-fibre-reinforced carbon composite material (CFC; abbreviated also as ‘C/C’ in English-spoken area of science) with a protective ceramic layer. Said layer, which covers the front of said material, is to be fastened via screw and nut, wherein the screw head is arranged in locking position on the ceramic layer, while the screw reaches across the ceramic layer and the subsequent layer of carbon-fibre-reinforced carbon composite material; a nut provides a tight, stable position of said screw, said nut being fastend on the rear surface of the carbon-fibre-reinforced carbon composite material. By positioning the ceramic layer on top of the carbon composite material the greater, thermal expansion of the ceramic material can not induce any tension or warping of the carbon composite body, while also avoiding any direct contact of a metal workpiece along the frontal surface. Furthermore, any tension or warping via the attached screw is avoided likewise, because screw and nut also have a greater thermal expansion than the carbon composite body.
A special disadvantage of this construction is however that upon reaching high temperature screw and nut—due to their greater thermal expansion—are no longer in tightly locked arrangement. The nut is no longer tightly attached to the rear side of the carbon composite body. Thus, said nut is loose at high temperatures. Furthermore, the loose arrangement of screw and nut will result in damaging impacts in case of vibrations: carbon composite body as well as ceramic layer will be prone to repeated, destructive impacts. Additionally, said nut is capable of free rotation at high temperature and may twist off the screw completely, resulting in complete failure of the fixation.
Likewise to the designations known from reinforced fibre composites, where a composite of two fibres of differing nature like metal/plastic are designated as ‘hybrid fibre composite’, such a grating combining a carbon composite body and fastened, ceramic spacers may be designated as ‘hybrid grating’. The combination of the two materials provide a reliable, high temperature stable, grating, i. e. a high-temperature-grating 10.
Likewise to the predescribed JP 07 133 166 the document DE 103 12 802 proposes                either to provide a monolithic, three dimensionally contoured workpiece-carrier with an additional groove obtained by milling        or to obtain a horizontal, plane grating by assembling mutually engaging board-strips of carbon-fibre-reinforced carbon material, said board-strips having comb-like cut-out sections on one side, wherein a board-strip within the grating may have an additional cut-out-section or groovesaid groove/cut-out-section shaped to receive a ceramic workpiece-support. The additional cut-out section is arranged parallel the top-side of the grating and may removably receive a ceramic workpiece-support, said workpiece-support having an upper section to support the respective workpiece and a lower section to be inserted into the enclosing cut-out section. In order to secure a workpiece-support in a required position or at a required height, this document teaches to connect it to the respective board-strip via a screw and/or to assemble the ceramic workpiece-support of different, matching parts, which allow an adjustment of height.In view of the predescribed disadvantages, securing a workpiece-support via an additional screw will also lead to the predescribed damages in case of vibrations. Likewise said screw will suffer the danger of turning loose and may damage the carbon composite body. Furthermore the weight of the dense ceramic will be transduced into all cross-wise oriented, comb-shaped elements, which means, that in case of impact or jarring impulse whole groups of elements will be subject to an improved, jarring, removing impulse, which may remove a complete group of elements from the grating. Especially in case of automatically handling the workpiece-carrier an impact, twist or flip will result in single, top-side comb-elements being completely removed from the grating due to the increased weight of attached, ceramic workpiece-support. Such a workpiece-carrier can only be handled safely, if it is enclosed completely along its whole bottom and kept in horizontal orientation without vibration. Otherwise, single elements may fall out of the grating. Any twist or turn of such a workpiece-carrier—especially a flip in an overhead-position—has to be avoided at all costs. The respective machines to provide such are finely adjustable and therefore very expensive.        
A special disadvantage is that single workpiece-supports will be able to fall out of their enclosure in case of fracture or fissure. The free falling, ceramic shards will then induce further impacts and damaging forces in devices underneath the grating, e. g. they will damage workpieces, workpiece-carriers or conveyor-mechanics situated beneath said grating.
A special disadvantage is that ceramic workpiece-supports having grooves, notches or under-cuts are prone to cracking during cool-down if additionally subjected to the weight of a supported workpiece. They will have to be exchanged frequently, incurring further costs. Especially in the case of additional vibrations, impacts or jolts such workpiece-supports showed considerable wear and respective rise in costs, as these supports were prone to cracking along their grooves and/or under-cuts at least every second use, resulting in disintegration, separation and further damage in every third to fourth use.A special disadvantage is that workpiece-supports according to the prior art will only provide additional support for a workpiece of irregular shape or raised center of gravity if arranged in a monolithic workpiece-carrier having a contoured shape, so as to provide workpiece-supports at differing height and position.